Implement ScalarValue::IntervalMonthDayNano -> String Support

[phillipleblanc]

Is your feature request related to a problem or challenge?

Part of #9494 to complete support for Unparsing LogicalPlan to SQL String.

Converting LogicalPlans back to SQL is valuable for several usecases such as using DataFusion in federated databases (e.g. generate SQL to push down) or using DataFusion's expr APIs to programmatically create SQL.

Describe the solution you'd like

Support converting SQL syntax that includes predicates with scalar values, like the following TPCH query:

select
    o_orderpriority,
    count(*) as order_count
from
    orders
where
        o_orderdate >= '1993-07-01'
  and o_orderdate < date '1993-07-01' + interval '3' month
  and exists (
        select
            *
        from
            lineitem
        where
                l_orderkey = o_orderkey
          and l_commitdate < l_receiptdate
    )
group by
    o_orderpriority
order by
    o_orderpriority;

The logical plan derived from parsing the above query should be able to be turned back into SQL.

Describe alternatives you've considered

The basic pattern is:

Implement the Expr --> AST reverse code in Unparser::expr_to_sql(source link)
Add a test to expr_to_sql_ok
Note you can run the tests like

cargo test -p datafusion-sql -- expr_to_sql_ok

Additional context

No response